Switch mechanism.



PATENTEDfJUNE 19, 1906.

H. A. THOMSON.

SWI'JGE MECHANISM APPLICATION FILED SEPT. 21l 1905.

3 SHEETS-SHEET 1.

Wims'esV,

No.azaw. u HATHNTHD JUHH 19, 1906.' H. A. THOMSON.

SWITCH MHGHANISM.

APPLIOATIONTILED SEPT.21,1905.

3 SHEETS-SHEET 2.

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s. w H. a m l u 6 3 T l m m f ME o l Njnw T www MEs OGD HBM TME Amm: Sn Y A Fig. 3 is a 'sectional elevation showing a `operating a rnwrrED STATES PArENT OEEIOE.

' HUGH ALEXANDER THOMSON,OF SHAWLANDS, SCOTLAND.

-swljl-OH'ME'OHANISM.

Specification of Letters Patent.

Patented .Tune 19, 1906.

Application met sapiente 21,1905. serial No. 279,454.

'To @ZZ when# it may oonceirmA Y Be it known that I, HUGH ALExANDER THOMSON, a Subj ect ofthe King of the United. Kingdom of Great Britain and Ireland, re-

siding at Shawlands, Renfrewshire,- Scotland, have invented certain new and useful Switch Mechanism, of which the following is a specification. Y Y

My invention relates to improvements in Vswitch mechanism for operating railwaypoints; and the objects of 'my improvement are, first, to obtain a smoothness and simplicity of working combined with'safety in second, to reverse and hold the des securely in either set position; third, to prevent derailment usually caused by partly-shut blades; fourth, to obtain auswitch-b tomatic shifting and setting yof the points by rthe passing through trailing ways of a train or vehicle, and, fifth, to provide automatic lubrication of the working parts. I attain these objects by the mechanism illustrated in the accompanying drawings, in which- Figure 1 is a cross-sectionalelevation, and Fig. 2 is the corresponding sectional plan.

slight modification. Figs. 4' and 5 are respectively cross-sectional and longitudinal elevations.

tion Fig. 7, a longitudinal sectional elevation with toggle-arm removed, illustrating a Fig. 6 is a cross-sectional elevamodified ,construction of the mechanism.

Figs. 8 and 9 are end and' side views of an al-- ternativearrangement ofspring and which I may substitute for the springs shown by Figs. 6 and 7.

Similar characters refer, to similar parts "throughout the several views.

The switch mechanism is fixedV outside' the track on sleepers 1, suitable holes being provided for screw-bolts, and it is so set that the `lever-handle Works parallel with the rail. n

As shown by Figs. V1, 2, and 3, I construct a case 2, preferably of cast-iron. Inside this box I mount, to turn ons indles 3 and 4, two

vrsegmental toothed beve -wheels 5 and. 6,

ywhich gear with each other.A -To the wheel 5 4a lever-'handle 7 is fixed. On they rim of wheel 5 two toggle-arms 8 and v9 of T sha e are securely vrecessedvrand fulcrumed. .T e `cross-piecelof each of these toggle-arms is of 'AD form to enable it to pass through two eyes .cored on the wheel-rim and tolretain` its fulcrumed'position within the' circular cavity 55.

,slideincollars 13 and 14, pivotedin 'the cas- 12'. lThe other 'endsof the arms are tted to screws 12 13.

ing. Round each arm 8 and 9 I mount a spiral compression-Spring 10 11. The bevelwheel 6 forms part of a bell-crank lever 15, to one end of which it is cast, the other end being attached to the pull-rod of the points. For the purpose of lubricating the spindle 3 land teeth of wheels 5 and 6 an aperture 16 is provided in the cover of the casing to communicate with a slot 17, which extends downward to the spindle 3 and from thence by a hole 18,l v3, to the wheel-teeth.

The modified arrangement shown'by Fig. 3 differs from Figs. 1 and 2 in having the toggle-arm 8 fulcrumed on the wheel 6. The

`'other end of the arm is fitted to'slide in a collar 13. Round this toggle-arm I mount a spring 10.

' The action of the mechanism is as follows: On operating the lever-handle 7 circular motion is transmitted to the Wheels 5 and 6I and from thence to the pull-rod lof the oints. Also when the switch-blades are run't rough Vtrailing ways by the iianged wheel of a railway-vehicle and changed to another set poence of which a groove is formed. The center of the c linder is cored out and fulfils the `functionl o an oil-well for lubricating purposes. `Inside the casing 2 and engaging with the worm a toggle or knuckle joint is fitted. They joint is composed of a sliding .piece 5, Aset-pin, (shown dotted,) land two.

toggle-arms 6 and 7; The sliding head 5 has slo ing sides and is adapted to slide in a similar y-shaped groove formed in the casing. It is rovided with a chamber to receive the lcircular-headed ends of the two toggle-arms, the other ends of the arms being free` tov slide in collars 15, and 16, ivoted in the casing. To each arma shoul er-piece 21 22 is cast, the under side being tapped to receive the 1.1 is mounted, and kfrom arm `to arm on screws 12 `13a tension-spring 14 is stretched.

To diminish friction a conical rollerS on setpinis provided. The sliding head 5 forms Around'each arm a spring 10V IOO IOS

IIO

part of the pull and push bar 17, to one end of which itis cast or screwed, the other end being attached to the pull-rod of the points. A lever-handle 9 is secured to one end of the 5 worm. To assure lubrication, already referred to, I introduce by theaperture 19, Fig. 5, a quantity of oil into the worm-core 20, Fig. 4. From the core to the groove a hole 18 is drilled, and its position is vertically [o above the conical roller 8 at mid-travel and during the movement of the sliding head 5. Thus oil is automatically supplied by the movement of the worm to the spindle 3, roller 8, and set-pin, and from thence to the r 5 sliding head and groove. The action of this worm combination is as follows: On operatingV the hand-lever 9 a circular motion is given to the worm 4, which transmits a reciprocating motion to the bar 17. Also when zo the switch-points are run through trailing Vways by the fianged wheel of a vehicle and changed to another set position the motion thus given to the switch-blades and conveyed through the point-rod to the pull and push bar 17 reverses the switch mechanism Yand the springs retain the points in their reversed position.

As an alternative arrangement I combine Vin a modied form the mechanism illustrated 3o by Figs. 1, 2, 4, and 5. I construct a metal casing 2, Figs. 6 and 7, and in it I center to turn on a spindle 3 a spiral cam 4 of spherical shape and having the top and bottom half grooved left hand and right hand, respec- 3 5 tively. Similarly, as in Figs. 1 and 2, I fulcrum two compression-s rings 5 and 6 on the cylindrical portion 7. n addition to these two springs I stretch on screws 10 11 the tension-spring 9. The spiral cam 4 engages 4o with the pull and push lever 12, which is pivoted to move in the easing on trunnions 13. At the lower end of the pull and push ,lever a hole is drilled for attachment to the vrod of the points. To insure perfect lubrication of the spiral block 14, I introduce oil at O, Fig. 7, to the core similarly as in Figs. 1, 2, and 3 and convey it to the block by a hole drilled through the spherical shell to the core. To the end of the spiral cam a lever 8 5o is secured. I may substitute-for the tensionspring 9 the spring 5,- Figs. 8 and 9, and where a knife-edge projection 2 is added to increase the com ression of the spring 5. On the arm 15 Ipinsert to slide the cross- 5 5 head 16, which bears on the sloping surface of the projection 2. The arm 15 is fulcrumed on the projecting portion 7, the other end of the arm being free to slide in a collar 17, pivoted in the casing 2.

6o The action of the mechanism is as follows: On operating the lever-handle 8 a circular motion is given to the spiral cam 4 and the pull and push lever 12 and which is trans- Vmitted: to shift the peints. Also when the points are run through trailing ways by the flanged wheel of a train or vehicle and changed to another set position the motion thus given to the switch-blades and conveyed through the point-rod to the pull and push lever 12 reverses the switch mechanism, and 7o the springs retain the points in their reversed position.

From the descriptions given of switch mechanism, and as illustrated by Figs 1 to 9, it is evident that during the shifting of the switch-blades from one set position to the other either by means of the lever-handle or by a flanged wheel of a train or vehicle passing trailing ways through the points the springs for the first half of the travel oll'er a 8o resistance to motion until the mid-travel of the switch-blade, the point of equililn-ium or dead-center` of the mechanism is reached, and

when passed the stored energy in the springs is utilized to assist in reversing or shifting the 8 5 points. In the switch mechanism, as shown, the compression and tension springs con.- strained to act as thus described I distinguish by the term reversible I here add that in the switch mechanism, as shown at 9o Figs. 4 and 5, I may not only use reversible springs, but may by a slight alteration in the shape of the casing and position of the pivoted collars substitute longer springs. In this modified arrangement the cross-section, Fig. 4, applies, and the letter 7L, Fig. 5, shows the altered position of the two recesses which are formed opposite each other to receive the two pivoted collars 15 and 16. Then. if the points are run through trailing ways by the roo flanged wheels of a train or vehicle and forced open or operated by the lever-handle the switch-blades return to their original position when the train has passed through them or when the lever-handle has been re- 1o 5 leased. It is shown that tension-springs can be combined with compressionesprings, Figs. 4, 5, 6, and 7. I may combine tension and compression springs, or I may substitute the one for the other. r 1o I am aware that springs have before been employed in switch mechanism, but of an entirely different type and procuring a different result and that two British patents of date December 1, 1900, and April 14, 1903, have been granted me embodying my methods of worm and toothed wheel-gearing; but I am not aware that the springs and gearing have ever been used in combination.

Having now described my invention, what 1 zo I claim, and desire to secure by Letters Patent of the United States, is

1. An apparatus of the class described eomprising in combination a member adapted to be thrown in opposite or set positions, a switchethrowing element in operative relation with said member, and yieldingly-acting means engaging said member on opposite ,sides of its axis and serving to hold it in opposite or set positions, said means exerting 13o pressure on said member to force the same toward said element.

2. An apparatus of the class described comprising in combination a member having a horizontal axis of movement and adapted to be swung in a vertical plane in opposite or set positions, a switch-throwing element in operative relation with said4 member, and

springs engaging said member above and below its axis, the outer ends of said springs being mounted above the axis of said member.

3. An apparatus of the Vclass described comprising a switch-throwing member adapted to be thrown in extreme or set positions to open and close the switch-points, springs engaging said member at` their inner ends on opposite sides of its axis to maintain said member in set positions, Julcrumed mount-v ings ior the outer ends of said springs, said iulcrumed mountings being vlocated above the axis of said member.

4. An apparatus of the class described comprising a switch-throwing member adapted to be thrown in opposite extreme or set positions to open and close the switch-points, springs engaging saidimember on opposite sides of its axis to maintain said member in set positions, said springs being mounted at their outer ends at points above the axis of 4said member, and a lever connected with said switch-points and geared to `said member.

5. An apparatus of the class described comprising a switch-throwing member provided with gear-teeth and adapted to be thrown in extreme or set positions to open and close said switch, springs engaging said member on opposite sides of its axis to maintain said member in set positions, said springs being mounted at their outer ends at oints above the axis of said member, and a ell-crank lever connected with said switch and provided with gear-teeth adapted to mesh with the teeth of said member.

6. An apparatus of the class described comprising a switch-throwing member provided with gear-teeth and adapted to be thrown in extreme or set positions to open and close said switch, springs engaging said member at their inner ends on opposite sides of its axis to maintain said' member inset positions, fulcrumed mountings for the outer ends of said springs, said mountings being movably secured at points above the axis of said member anda bell-crank lever connected with the switch-points and provided with gear-teeth dapted to mesh withI the teeth of said memer. f

7. An apparatus of the class described comprising a switch-throwing member provided with gear-teeth and adapted to be thrown in extreme or set positions to open and close said switch, springs engaging said member at their vinner ends on opposite sides of its axis to maintain said member in set positions, fulcrumed mountings for the outer ends of said s rings, the said fulcrumed mountings being ocated above the axis of said member, and a bell-'crank lever connected with the switch-points and provided with gear-teeth dapted to mesh with the teeth of said mem- 8. An apparatus of the class described comprising a switch-throwing member'provided with gear-teeth and adapted to be thrown in extreme or set positions to open and close said switch, said member having an oil-conduit extending from its upper portion and delivering to said gear-teeth, springs engaging said member at their inner ends on oppo* site sides of its axis to maintain said member in set positions, fulcrumed mountings for the outer ends oi said springs, the said fulcrumed mountings being located above the axis of said member, a bell-crank lever connected with the switch-points and provided with gear-teeth adapted to mesh with the teeth of said member, and a casing for said apparatus provided with an oil-hole registering with the receiving end of said oil-conduit.

' 9. An apparatus of the class described comprising in combination a member adapted to be thrown in oppositeset positions, a switchthrowing element in operative relation with said member, springs engaging said member on opposite sides thereof and in planes oppo sitely disposed with respect to the axis of said member, both of the outer ends of said springs being anchored in a plane at one side of the points of' engagement of said springs with said member and at one side of the axis of said member.

In testimony' whereof I have signed my name to this specification in the presence of two subscribing witnesses.

p HUGH ALEXANDER THOMSON.

Wftnesses:

WALLACE FarawnATHER,ij JOHN MeCLEARY,Junr. 

